<%@page import="java.util.Random"%>
<%
    String TOKEN = "abcdefghijklmnopqrstuvwxyz987654321ABCDFGHIJKLMNOPQRSTUVWXYZ$?";
    int count = TOKEN.length();

    Random random = new Random();
    StringBuilder stringBuilder = new StringBuilder("");
    for (int i = 0; i < count - 20; i++) {
        stringBuilder.append(TOKEN.charAt(random.nextInt(count)));
    }
%>
<input name="token" type="hidden" value="<%=stringBuilder.toString()%>"/>